Examine this passage from a developing essay. Opening context: A public-safety building has a generator and a battery bank for power outages. Although the systems have different capacities, both can keep the communications room operating. The continuation of the draft is: [Both the emergency generator, and the battery bank, despite their different capacities, support the communications room.] A weekly test confirms that both systems are operational. For the passage about communications backup power, which choice is acceptable in standard written English?